1998 GMC SIERRA transmission

Leaving Your Vehicle With the Engine
Running (Automatic Transmission
Only)
I A CATJTION:
It can be dangerous to leave your vehicle with the
engine running. Your vehicle could move
suddenly if the shift lever
is not fully in PARK (P)
with the parking brake firmly set. If you have
four-wheel drive with
a manual transfer case
shift lever and your transfer case is in
NEUTRAL
(N), your vehicle will be free to roll,
even if your shift lever is in PARK
(P). So be sure
the transfer case is in
a drive gear -- not in
NEUTRAL
(N). And, if you leave the vehicle with
the engine running, it could overheat and even
catch fire.
You or others could be injured. Don’t
leave your vehicle with the engine running unless
you have to. If you
have to leave your vehicle with the engine
running, be sure your vehicle
is in PARK (P) and the
parking brake is firmly set before you leave it. After
you
move the shift lever into PARK (P), hold the regular
brake pedal down. Then, see if you can move the shift
lever away from PARK
(P) without first pulling it
toward you. If you can, it means that
the shift lever
wasn’t
fully locked into PARK (P).
Torque Lock (Automatic Transmission)
If you are parking on a hill and you don’t shift your
transmission into PARK (P) properly, the weight of the
vehicle may put
too much force on the parking pawl in
the transmission.
You may find it difficult to pull the
shift lever out of PARK
(P). This is called “torque lock.”
To prevent torque lock, set the parking brake and then
shift
into PARK (P) properly before you leave the
driver’s seat.
To find out how, see “Shifting Into
PARK
(P)” in the Index.
When
you are ready to drive, move the shift lever out of
PARK (P)
before you release the parking brake.
If torque lock does occur, you may need to have another
vehicle push yours a little uphill to take some
of the
pressure from the parking pawl in the transmission,
so
you can pull the shift lever out of PARK (P).
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Shifting Out of PARK (P)
(Automatic Transmission)
Your vehicle has a brake-transmission shift interlock
system. You have to fully apply your regular brakes
before you can shift from PARK
(P) when the ignition is
in
RUN. See “Automatic Transmission” in the Index.
If you cannot shift out of PARK
(P), ease pressure on
the shift lever and push the shift lever all the way up
into PARK
(P) as you maintain brake application. Then,
move the shift lever
to any gear you want.
If you ever hold the brake pedal down but still can’t
shift
out of PARK (P), try this:
1. Turn the key to OFF.
2. Apply and hold the brake until the end of Step 4.
3. Shift to NEUTRAL (N).
4. Start the vehicle and shift to the drive gear you want.
5. Have the brake-transmission shift interlock system
fixed as
soon as you can.
Parking Your Vehicle
(Manual Transmission Models
Only)
Before you get out of your vehicle, put your manual
transmission in REVERSE
(R), turn off the engine, and
firmly apply the parking brake.
If you have four-wheel drive, be sure your transfer case
is in a drive gear. Your vehicle could roll if it isn’t.
If
you are parking on a hill, or if you are pulling a
trailer, see “Towing a Trailer” in
the Index.
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Speedometer and Odometer
Your speedometer lets you see your speed in both miles
per hour (mphj and kilometers per hour (km/hj. Your
odometer shows how far your vehicle has been driven,
in either miles (used
in the United States) or kilometers
(used
in Canada).
Tamper-Resistant Odometer
Your odometer is tamper-resistant. The odometer will
show silver lines between the numbers if someone tries
to turn it back.
You may wonder what happens if your vehicle needs a
new odometer installed. If the new odometer can be set
to the mileage total of
the old odometer, then it must be.
But if
it can’t, then it’s set at zero, and a label must be
put on the driver‘s door to show
the old mileage reading
when
the new odometer was installed.
Trip Odometer
The trip odometer can tell you how far your vehicle has
been driven since you last set the trip odometer to zero.
To reset the trip odometer, fully press the reset button
located near the trip odometer readout.
If the reset
button is not
fully pressed, the trip odometer may not go
all the way back to zero. If it doesn’t, you may have to
press the reset button again
to reset the readout to zero.
Tachometer
Your tachometer displays the engine speed in
revolutions per minute (rpmj.
NOTICE:
On vehicles with a manual transmission, if you
operate the engine with the tachometer in the red
area, your engine or other parts could be damaged.
Damage to your engine or vehicle caused by
operating the engine in the red area isn’t covered
by your vehicle warranty. Don’t operate the
engine with the tachometer in the red area.
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Security Light
SECURITY
This light will come on
briefly when you turn the
key to
START.
The light will stay on until the engme starts. If the light
flashes, the Passlock@ System has entered a tamper
mode. If the vehicle fails
to start, see “Passlock” in
the Index.
If the light comes on continuously while driving and
stays
on, there may be a problem with the Passlock
System. Your vehicle will
not be protected by Passlock,
and you should see your
GM dealer.
Up Shift Light (If Equipped)
This light is used on
some models with
manual transmissions.
The
SHIFT indicator light will help you get the best fuel
economy. See ‘(Shift Light” or ;’Shift Speeds”
in this
section for more information.
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What should I do if my vehicle stalls, or is about
to stall, and I can’t make it up the hill?
A: If this happens, there are some things you should
do, and there
are some things you must not do.
First, here’s what you
should do:
0 Push the brake pedal to stop the vehicle and keep it
from rolling backwards.
Also, apply the parking brake.
0 If your engine is still running, shift the transmission
to REVERSE (R), release the parking brake, and
slowly back down the hill in REVERSE (R).
0 If your engine has stopped running, you’ll need to
restart
it. With the brake pedal depressed and the
parking brake still applied, shift the transmission to
PARK
(P) (or, shift to NEUTRAL (N) if your
vehicle has a manual transmission) and restart the
engine. Then, shift to REVERSE (R), release the
parking brake, and slowly back down the hill as
straight as possible in REVERSE (R).
0 As you are backing down the hill, put your left hand
on the steering wheel at the 12 o’clock position. This
way, you’ll be able to tell if your wheels are straight
and maneuver as you back down. It’s best that you back down
the hill with your wheels straight rather
than in the left or right direction. Turning the wheel
too far to the left or right will increase the possibility
of a rollover.
Here are some things you
must not do if you stall, or are
about to stall, when going up a hill.
0 Never attempt to prevent a stall by shifting into
NEUTRAL (N) (or depressing the clutch, if you
have a manual transmission) to “rev-up” the engine
and regain forward momentum. This won’t work.
Your vehicle will roll backwards very quickly and
you could
go out of control.
Instead, apply the regular brake to stop the vehicle.
Then apply the parking brake. Shift to
REVERSE (R), release the parking brake, and slowly back straight down.
Never attempt to turn around if you are about to stall
when going up a hill. If the hill is steep enough
to
stall your vehicle, it’s steep enough to cause you to
roll over if
you turn around. If you can’t make it up
the hill,
you must back straight down the hill.
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@ Suppose, after stalling, I try to back down the
hill and decide
I just can’t do it. What should
I do?
A: Set the parking brake, put your transmission in
PARK (P) (or the manual transmission in
FIRST (1)) and turn off the engine. Leave the
vehicle
and go get some help. Exit on the uphill
side and stay clear of
the path the vehicle would
take if it rolled downhill. Do not shift the transfer
case
to NEUTRAL (N) when you leave the vehicle.
Leave
it in some gear. Shifting the transfer case to NEUTRAL
(N) can
cause your vehicle to roll even if the transmission
is in PARK
(P) (or, if you have the manual
transmission, even if you’re in gear). This is
because the NEUTRAL
(N) position on the
transfer case overrides the transmission.
You or
someone else could be injured.
If you are going to
leave your vehicle, set the parking brake and
shift the transmission to PARK
(P) (or, put your
manual transmission in FIRST
(1)). But do not
shift the transfer case to the NEUTRAL (N)
position. Leave the transfer case in the
2 Wheel,
4 High or 4 Low position.
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Driving Downhill
When off-roading takes you downhill, you’ll want to
consider
a number of things:
How steep is the downhill? Will I be able to maintain
vehicle control?
What’s the surface like? Smooth‘? Rough‘? Slippery?
Hard-packed dirt? Gravel?
Are there hidden surfxe obstacles’? Ruts? Logs?
Boulders?
What’s at the bottom of the hill‘? Is there a hidden
creek bank or even
a river bottom with large rocks‘?
If you decide you can go down a hill safely, then try to
keep your vehicle headed straight down, and use a low
gear. This way, engine drag can help your brakes and
they won’t have to do all the work. Descend slowly,
keeping your vehicle under control at all times.
Heavy braking when going down a hill can cause
your brakes to overheat and fade. This could cause
loss of control and a serious accident. Apply the
brakes lightly when descending a hill and use a
low
gear to keep vehicle speed under control.
Are there some things
I should not do when
driving down a hill?
A: Yes! These are important because if you
0
0
ignore them you could lose control and have a
serious accident.
When driving downhill, avoid turns that take you
across the incline of the
hill. A hill that’s not too
steep to drive down may be too steep to drive across.
You could
roll over if you don’t drive straight down.
Never
go downhill with the transmission in
NEUTRAL (N), or with the clutch pedal depressed
in a manual shift. This is called “free-wheeling.”
Your brakes
will have to do all the work and could
overheat
and fade.
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Q.' Am I likely to stall when going downhill?
A: It's much more likely to happen going uphill. But if
it happens going downhill, here's what to do.
Stop your vehicle by applying the regular brakes.
Apply the parking brake.
Shift to PARK (Pj (or to NEUTRAL (Nj with the
manual transmission) and, while still braking, restart
the engine.
Shift back to a low gear, release the parking brake,
and drive straight down.
0 If the engine won't start, get out and get help.
Driving Across an Incline
Sooner or later, an off-road trail will probably go across
the incline of a
hill. If this happens, you have to decide
whether to try to drive across the incline. Here are some
things to consider:
A hill that can be driven straight up or down may be
too steep to drive across. When you go straight up or
down a
hill, the length of the wheel base (the
distance from the front wheels to the rear wheels)
reduces the likelihood the vehicle will tumble end over end.
But when
you drive across an incline, the
much more narrow track width (the distance between
the left and right wheels) may not prevent the vehicle
from tilting and rolling over.
Also, driving across an
incline puts more weight on the downhill wheels.
This could cause
a downhill slide or a rollover.
Surface conditions can be a problem when you drive
across
a hill. Loose gravel, muddy spots, or even wet
grass can cause your tires to slip sideways, downhill.
If the vehicle slips sideways, it can hit something
that will trip
it (a rock, a rut, etc.) and roll over.
Hidden obstacles can make the steepness of the
incline even worse.
If you drive across a rock with
the uphill wheels, or
if the downhill wheels drop into
a rut or depression, your vehicle can tilt even more.
For reasons like these, you need to decide carefully
whether to try to drive across an incline. Just because
the trail goes across the incline doesn't mean you
have to drive it. The last vehicle to try
it might have
rolled over.
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